Connect Configurations

This topic provides configuration parameters available for Confluent Platform. The parameters are organized by order of importance, ranked from high to low.

  • config.storage.topic

    The name of the Kafka topic where connector configurations are stored

    Type:string
    Default:
    Valid Values:
    Importance:high
  • group.id

    A unique string that identifies the Connect cluster group this worker belongs to.

    Type:string
    Default:
    Valid Values:
    Importance:high
  • key.converter

    Converter class used to convert between Kafka Connect format and the serialized form that is written to Kafka. This controls the format of the keys in messages written to or read from Kafka, and since this is independent of connectors it allows any connector to work with any serialization format. Examples of common formats include JSON and Avro.

    Type:class
    Default:
    Valid Values:
    Importance:high
  • offset.storage.topic

    The name of the Kafka topic where connector offsets are stored

    Type:string
    Default:
    Valid Values:
    Importance:high
  • status.storage.topic

    The name of the Kafka topic where connector and task status are stored

    Type:string
    Default:
    Valid Values:
    Importance:high
  • value.converter

    Converter class used to convert between Kafka Connect format and the serialized form that is written to Kafka. This controls the format of the values in messages written to or read from Kafka, and since this is independent of connectors it allows any connector to work with any serialization format. Examples of common formats include JSON and Avro.

    Type:class
    Default:
    Valid Values:
    Importance:high
  • bootstrap.servers

    A list of host/port pairs to use for establishing the initial connection to the Kafka cluster. The client will make use of all servers irrespective of which servers are specified here for bootstrapping—this list only impacts the initial hosts used to discover the full set of servers. This list should be in the form host1:port1,host2:port2,.... Since these servers are just used for the initial connection to discover the full cluster membership (which may change dynamically), this list need not contain the full set of servers (you may want more than one, though, in case a server is down).

    Type:list
    Default:localhost:9092
    Valid Values:
    Importance:high
  • heartbeat.interval.ms

    The expected time between heartbeats to the group coordinator when using Kafka's group management facilities. Heartbeats are used to ensure that the worker's session stays active and to facilitate rebalancing when new members join or leave the group. The value must be set lower than session.timeout.ms, but typically should be set no higher than 1/3 of that value. It can be adjusted even lower to control the expected time for normal rebalances.

    Type:int
    Default:3000
    Valid Values:
    Importance:high
  • rebalance.timeout.ms

    The maximum allowed time for each worker to join the group once a rebalance has begun. This is basically a limit on the amount of time needed for all tasks to flush any pending data and commit offsets. If the timeout is exceeded, then the worker will be removed from the group, which will cause offset commit failures.

    Type:int
    Default:60000
    Valid Values:
    Importance:high
  • session.timeout.ms

    The timeout used to detect worker failures. The worker sends periodic heartbeats to indicate its liveness to the broker. If no heartbeats are received by the broker before the expiration of this session timeout, then the broker will remove the worker from the group and initiate a rebalance. Note that the value must be in the allowable range as configured in the broker configuration by group.min.session.timeout.ms and group.max.session.timeout.ms.

    Type:int
    Default:10000
    Valid Values:
    Importance:high
  • ssl.key.password

    The password of the private key in the key store file. This is optional for client.

    Type:password
    Default:null
    Valid Values:
    Importance:high
  • ssl.keystore.location

    The location of the key store file. This is optional for client and can be used for two-way authentication for client.

    Type:string
    Default:null
    Valid Values:
    Importance:high
  • ssl.keystore.password

    The store password for the key store file. This is optional for client and only needed if ssl.keystore.location is configured.

    Type:password
    Default:null
    Valid Values:
    Importance:high
  • ssl.truststore.location

    The location of the trust store file.

    Type:string
    Default:null
    Valid Values:
    Importance:high
  • ssl.truststore.password

    The password for the trust store file. If a password is not set access to the truststore is still available, but integrity checking is disabled.

    Type:password
    Default:null
    Valid Values:
    Importance:high
  • client.dns.lookup

    Controls how the client uses DNS lookups. If set to use_all_dns_ips then, when the lookup returns multiple IP addresses for a hostname, they will all be attempted to connect to before failing the connection. Applies to both bootstrap and advertised servers. If the value is resolve_canonical_bootstrap_servers_only each entry will be resolved and expanded into a list of canonical names.

    Type:string
    Default:default
    Valid Values:[default, use_all_dns_ips, resolve_canonical_bootstrap_servers_only]
    Importance:medium
  • connections.max.idle.ms

    Close idle connections after the number of milliseconds specified by this config.

    Type:long
    Default:540000
    Valid Values:
    Importance:medium
  • connector.client.config.override.policy

    Class name or alias of implementation of ConnectorClientConfigOverridePolicy. Defines what client configurations can be overriden by the connector. The default implementation is `None`. The other possible policies in the framework include `All` and `Principal`.

    Type:string
    Default:None
    Valid Values:
    Importance:medium
  • receive.buffer.bytes

    The size of the TCP receive buffer (SO_RCVBUF) to use when reading data. If the value is -1, the OS default will be used.

    Type:int
    Default:32768
    Valid Values:[0,...]
    Importance:medium
  • request.timeout.ms

    The configuration controls the maximum amount of time the client will wait for the response of a request. If the response is not received before the timeout elapses the client will resend the request if necessary or fail the request if retries are exhausted.

    Type:int
    Default:40000
    Valid Values:[0,...]
    Importance:medium
  • sasl.client.callback.handler.class

    The fully qualified name of a SASL client callback handler class that implements the AuthenticateCallbackHandler interface.

    Type:class
    Default:null
    Valid Values:
    Importance:medium
  • sasl.jaas.config

    JAAS login context parameters for SASL connections in the format used by JAAS configuration files. JAAS configuration file format is described here. The format for the value is: 'loginModuleClass controlFlag (optionName=optionValue)*;'. For brokers, the config must be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.scram-sha-256.sasl.jaas.config=com.example.ScramLoginModule required;

    Type:password
    Default:null
    Valid Values:
    Importance:medium
  • sasl.kerberos.service.name

    The Kerberos principal name that Kafka runs as. This can be defined either in Kafka's JAAS config or in Kafka's config.

    Type:string
    Default:null
    Valid Values:
    Importance:medium
  • sasl.login.callback.handler.class

    The fully qualified name of a SASL login callback handler class that implements the AuthenticateCallbackHandler interface. For brokers, login callback handler config must be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.scram-sha-256.sasl.login.callback.handler.class=com.example.CustomScramLoginCallbackHandler

    Type:class
    Default:null
    Valid Values:
    Importance:medium
  • sasl.login.class

    The fully qualified name of a class that implements the Login interface. For brokers, login config must be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.scram-sha-256.sasl.login.class=com.example.CustomScramLogin

    Type:class
    Default:null
    Valid Values:
    Importance:medium
  • sasl.mechanism

    SASL mechanism used for client connections. This may be any mechanism for which a security provider is available. GSSAPI is the default mechanism.

    Type:string
    Default:GSSAPI
    Valid Values:
    Importance:medium
  • security.protocol

    Protocol used to communicate with brokers. Valid values are: PLAINTEXT, SSL, SASL_PLAINTEXT, SASL_SSL.

    Type:string
    Default:PLAINTEXT
    Valid Values:
    Importance:medium
  • send.buffer.bytes

    The size of the TCP send buffer (SO_SNDBUF) to use when sending data. If the value is -1, the OS default will be used.

    Type:int
    Default:131072
    Valid Values:[0,...]
    Importance:medium
  • ssl.enabled.protocols

    The list of protocols enabled for SSL connections.

    Type:list
    Default:TLSv1.2,TLSv1.1,TLSv1
    Valid Values:
    Importance:medium
  • ssl.keystore.type

    The file format of the key store file. This is optional for client.

    Type:string
    Default:JKS
    Valid Values:
    Importance:medium
  • ssl.protocol

    The SSL protocol used to generate the SSLContext. Default setting is TLS, which is fine for most cases. Allowed values in recent JVMs are TLS, TLSv1.1 and TLSv1.2. SSL, SSLv2 and SSLv3 may be supported in older JVMs, but their usage is discouraged due to known security vulnerabilities.

    Type:string
    Default:TLS
    Valid Values:
    Importance:medium
  • ssl.provider

    The name of the security provider used for SSL connections. Default value is the default security provider of the JVM.

    Type:string
    Default:null
    Valid Values:
    Importance:medium
  • ssl.truststore.type

    The file format of the trust store file.

    Type:string
    Default:JKS
    Valid Values:
    Importance:medium
  • worker.sync.timeout.ms

    When the worker is out of sync with other workers and needs to resynchronize configurations, wait up to this amount of time before giving up, leaving the group, and waiting a backoff period before rejoining.

    Type:int
    Default:3000
    Valid Values:
    Importance:medium
  • worker.unsync.backoff.ms

    When the worker is out of sync with other workers and fails to catch up within worker.sync.timeout.ms, leave the Connect cluster for this long before rejoining.

    Type:int
    Default:300000
    Valid Values:
    Importance:medium
  • access.control.allow.methods

    Sets the methods supported for cross origin requests by setting the Access-Control-Allow-Methods header. The default value of the Access-Control-Allow-Methods header allows cross origin requests for GET, POST and HEAD.

    Type:string
    Default:""
    Valid Values:
    Importance:low
  • access.control.allow.origin

    Value to set the Access-Control-Allow-Origin header to for REST API requests.To enable cross origin access, set this to the domain of the application that should be permitted to access the API, or '*' to allow access from any domain. The default value only allows access from the domain of the REST API.

    Type:string
    Default:""
    Valid Values:
    Importance:low
  • admin.listeners

    List of comma-separated URIs the Admin REST API will listen on. The supported protocols are HTTP and HTTPS. An empty or blank string will disable this feature. The default behavior is to use the regular listener (specified by the 'listeners' property).

    Type:list
    Default:null
    Valid Values:org.apache.kafka.connect.runtime.WorkerConfig$AdminListenersValidator@4520ebad
    Importance:low
  • client.id

    An id string to pass to the server when making requests. The purpose of this is to be able to track the source of requests beyond just ip/port by allowing a logical application name to be included in server-side request logging.

    Type:string
    Default:""
    Valid Values:
    Importance:low
  • config.providers

    Comma-separated names of ConfigProvider classes, loaded and used in the order specified. Implementing the interface ConfigProvider allows you to replace variable references in connector configurations, such as for externalized secrets.

    Type:list
    Default:""
    Valid Values:
    Importance:low
  • config.storage.replication.factor

    Replication factor used when creating the configuration storage topic

    Type:short
    Default:3
    Valid Values:[1,...]
    Importance:low
  • connect.protocol

    Compatibility mode for Kafka Connect Protocol

    Type:string
    Default:sessioned
    Valid Values:[eager, compatible, sessioned]
    Importance:low
  • header.converter

    HeaderConverter class used to convert between Kafka Connect format and the serialized form that is written to Kafka. This controls the format of the header values in messages written to or read from Kafka, and since this is independent of connectors it allows any connector to work with any serialization format. Examples of common formats include JSON and Avro. By default, the SimpleHeaderConverter is used to serialize header values to strings and deserialize them by inferring the schemas.

    Type:class
    Default:org.apache.kafka.connect.storage.SimpleHeaderConverter
    Valid Values:
    Importance:low
  • inter.worker.key.generation.algorithm

    The algorithm to use for generating internal request keys

    Type:string
    Default:HmacSHA256
    Valid Values:Any KeyGenerator algorithm supported by the worker JVM
    Importance:low
  • inter.worker.key.size

    The size of the key to use for signing internal requests, in bits. If null, the default key size for the key generation algorithm will be used.

    Type:int
    Default:null
    Valid Values:
    Importance:low
  • inter.worker.key.ttl.ms

    The TTL of generated session keys used for internal request validation (in milliseconds)

    Type:int
    Default:3600000
    Valid Values:[0,...,2147483647]
    Importance:low
  • inter.worker.signature.algorithm

    The algorithm used to sign internal requests

    Type:string
    Default:HmacSHA256
    Valid Values:Any MAC algorithm supported by the worker JVM
    Importance:low
  • inter.worker.verification.algorithms

    A list of permitted algorithms for verifying internal requests

    Type:list
    Default:HmacSHA256
    Valid Values:A list of one or more MAC algorithms, each supported by the worker JVM
    Importance:low
  • internal.key.converter

    Converter class used to convert between Kafka Connect format and the serialized form that is written to Kafka. This controls the format of the keys in messages written to or read from Kafka, and since this is independent of connectors it allows any connector to work with any serialization format. Examples of common formats include JSON and Avro. This setting controls the format used for internal bookkeeping data used by the framework, such as configs and offsets, so users can typically use any functioning Converter implementation. Deprecated; will be removed in an upcoming version.

    Type:class
    Default:org.apache.kafka.connect.json.JsonConverter
    Valid Values:
    Importance:low
  • internal.value.converter

    Converter class used to convert between Kafka Connect format and the serialized form that is written to Kafka. This controls the format of the values in messages written to or read from Kafka, and since this is independent of connectors it allows any connector to work with any serialization format. Examples of common formats include JSON and Avro. This setting controls the format used for internal bookkeeping data used by the framework, such as configs and offsets, so users can typically use any functioning Converter implementation. Deprecated; will be removed in an upcoming version.

    Type:class
    Default:org.apache.kafka.connect.json.JsonConverter
    Valid Values:
    Importance:low
  • listeners

    List of comma-separated URIs the REST API will listen on. The supported protocols are HTTP and HTTPS.
    Specify hostname as 0.0.0.0 to bind to all interfaces.
    Leave hostname empty to bind to default interface.
    Examples of legal listener lists: HTTP://myhost:8083,HTTPS://myhost:8084

    Type:list
    Default:null
    Valid Values:
    Importance:low
  • metadata.max.age.ms

    The period of time in milliseconds after which we force a refresh of metadata even if we haven't seen any partition leadership changes to proactively discover any new brokers or partitions.

    Type:long
    Default:300000
    Valid Values:[0,...]
    Importance:low
  • metric.reporters

    A list of classes to use as metrics reporters. Implementing the org.apache.kafka.common.metrics.MetricsReporter interface allows plugging in classes that will be notified of new metric creation. The JmxReporter is always included to register JMX statistics.

    Type:list
    Default:""
    Valid Values:
    Importance:low
  • metrics.num.samples

    The number of samples maintained to compute metrics.

    Type:int
    Default:2
    Valid Values:[1,...]
    Importance:low
  • metrics.recording.level

    The highest recording level for metrics.

    Type:string
    Default:INFO
    Valid Values:[INFO, DEBUG]
    Importance:low
  • metrics.sample.window.ms

    The window of time a metrics sample is computed over.

    Type:long
    Default:30000
    Valid Values:[0,...]
    Importance:low
  • offset.flush.interval.ms

    Interval at which to try committing offsets for tasks.

    Type:long
    Default:60000
    Valid Values:
    Importance:low
  • offset.flush.timeout.ms

    Maximum number of milliseconds to wait for records to flush and partition offset data to be committed to offset storage before cancelling the process and restoring the offset data to be committed in a future attempt.

    Type:long
    Default:5000
    Valid Values:
    Importance:low
  • offset.storage.partitions

    The number of partitions used when creating the offset storage topic

    Type:int
    Default:25
    Valid Values:[1,...]
    Importance:low
  • offset.storage.replication.factor

    Replication factor used when creating the offset storage topic

    Type:short
    Default:3
    Valid Values:[1,...]
    Importance:low
  • plugin.path

    List of paths separated by commas (,) that contain plugins (connectors, converters, transformations). The list should consist of top level directories that include any combination of:
    a) directories immediately containing jars with plugins and their dependencies
    b) uber-jars with plugins and their dependencies
    c) directories immediately containing the package directory structure of classes of plugins and their dependencies
    Note: symlinks will be followed to discover dependencies or plugins.
    Examples: plugin.path=/usr/local/share/java,/usr/local/share/kafka/plugins,/opt/connectors

    Type:list
    Default:null
    Valid Values:
    Importance:low
  • reconnect.backoff.max.ms

    The maximum amount of time in milliseconds to wait when reconnecting to a broker that has repeatedly failed to connect. If provided, the backoff per host will increase exponentially for each consecutive connection failure, up to this maximum. After calculating the backoff increase, 20% random jitter is added to avoid connection storms.

    Type:long
    Default:1000
    Valid Values:[0,...]
    Importance:low
  • reconnect.backoff.ms

    The base amount of time to wait before attempting to reconnect to a given host. This avoids repeatedly connecting to a host in a tight loop. This backoff applies to all connection attempts by the client to a broker.

    Type:long
    Default:50
    Valid Values:[0,...]
    Importance:low
  • rest.advertised.host.name

    If this is set, this is the hostname that will be given out to other workers to connect to.

    Type:string
    Default:null
    Valid Values:
    Importance:low
  • rest.advertised.listener

    Sets the advertised listener (HTTP or HTTPS) which will be given to other workers to use.

    Type:string
    Default:null
    Valid Values:
    Importance:low
  • rest.advertised.port

    If this is set, this is the port that will be given out to other workers to connect to.

    Type:int
    Default:null
    Valid Values:
    Importance:low
  • rest.extension.classes

    Comma-separated names of ConnectRestExtension classes, loaded and called in the order specified. Implementing the interface ConnectRestExtension allows you to inject into Connect's REST API user defined resources like filters. Typically used to add custom capability like logging, security, etc.

    Type:list
    Default:""
    Valid Values:
    Importance:low
  • rest.host.name

    Hostname for the REST API. If this is set, it will only bind to this interface.

    Type:string
    Default:null
    Valid Values:
    Importance:low
  • rest.port

    Port for the REST API to listen on.

    Type:int
    Default:8083
    Valid Values:
    Importance:low
  • rest.servlet.initializor.classes

    Defines one or more initializer for the rest endpoint's ServletContextHandler. Each initializer must implement Consumer. It will be called to perform initialization of the handler, in order. This is an internal feature and subject to change, including changes to the Jetty version

    Type:list
    Default:""
    Valid Values:
    Importance:low
  • retry.backoff.ms

    The amount of time to wait before attempting to retry a failed request to a given topic partition. This avoids repeatedly sending requests in a tight loop under some failure scenarios.

    Type:long
    Default:100
    Valid Values:[0,...]
    Importance:low
  • sasl.kerberos.kinit.cmd

    Kerberos kinit command path.

    Type:string
    Default:/usr/bin/kinit
    Valid Values:
    Importance:low
  • sasl.kerberos.min.time.before.relogin

    Login thread sleep time between refresh attempts.

    Type:long
    Default:60000
    Valid Values:
    Importance:low
  • sasl.kerberos.ticket.renew.jitter

    Percentage of random jitter added to the renewal time.

    Type:double
    Default:0.05
    Valid Values:
    Importance:low
  • sasl.kerberos.ticket.renew.window.factor

    Login thread will sleep until the specified window factor of time from last refresh to ticket's expiry has been reached, at which time it will try to renew the ticket.

    Type:double
    Default:0.8
    Valid Values:
    Importance:low
  • sasl.login.refresh.buffer.seconds

    The amount of buffer time before credential expiration to maintain when refreshing a credential, in seconds. If a refresh would otherwise occur closer to expiration than the number of buffer seconds then the refresh will be moved up to maintain as much of the buffer time as possible. Legal values are between 0 and 3600 (1 hour); a default value of 300 (5 minutes) is used if no value is specified. This value and sasl.login.refresh.min.period.seconds are both ignored if their sum exceeds the remaining lifetime of a credential. Currently applies only to OAUTHBEARER.

    Type:short
    Default:300
    Valid Values:[0,...,3600]
    Importance:low
  • sasl.login.refresh.min.period.seconds

    The desired minimum time for the login refresh thread to wait before refreshing a credential, in seconds. Legal values are between 0 and 900 (15 minutes); a default value of 60 (1 minute) is used if no value is specified. This value and sasl.login.refresh.buffer.seconds are both ignored if their sum exceeds the remaining lifetime of a credential. Currently applies only to OAUTHBEARER.

    Type:short
    Default:60
    Valid Values:[0,...,900]
    Importance:low
  • sasl.login.refresh.window.factor

    Login refresh thread will sleep until the specified window factor relative to the credential's lifetime has been reached, at which time it will try to refresh the credential. Legal values are between 0.5 (50%) and 1.0 (100%) inclusive; a default value of 0.8 (80%) is used if no value is specified. Currently applies only to OAUTHBEARER.

    Type:double
    Default:0.8
    Valid Values:[0.5,...,1.0]
    Importance:low
  • sasl.login.refresh.window.jitter

    The maximum amount of random jitter relative to the credential's lifetime that is added to the login refresh thread's sleep time. Legal values are between 0 and 0.25 (25%) inclusive; a default value of 0.05 (5%) is used if no value is specified. Currently applies only to OAUTHBEARER.

    Type:double
    Default:0.05
    Valid Values:[0.0,...,0.25]
    Importance:low
  • scheduled.rebalance.max.delay.ms

    The maximum delay that is scheduled in order to wait for the return of one or more departed workers before rebalancing and reassigning their connectors and tasks to the group. During this period the connectors and tasks of the departed workers remain unassigned

    Type:int
    Default:300000
    Valid Values:[0,...,2147483647]
    Importance:low
  • ssl.cipher.suites

    A list of cipher suites. This is a named combination of authentication, encryption, MAC and key exchange algorithm used to negotiate the security settings for a network connection using TLS or SSL network protocol. By default all the available cipher suites are supported.

    Type:list
    Default:null
    Valid Values:
    Importance:low
  • ssl.client.auth

    Configures kafka broker to request client authentication. The following settings are common:

    • ssl.client.auth=required If set to required client authentication is required.
    • ssl.client.auth=requested This means client authentication is optional. unlike requested , if this option is set client can choose not to provide authentication information about itself
    • ssl.client.auth=none This means client authentication is not needed.

    Type:string
    Default:none
    Valid Values:
    Importance:low
  • ssl.endpoint.identification.algorithm

    The endpoint identification algorithm to validate server hostname using server certificate.

    Type:string
    Default:https
    Valid Values:
    Importance:low
  • ssl.keymanager.algorithm

    The algorithm used by key manager factory for SSL connections. Default value is the key manager factory algorithm configured for the Java Virtual Machine.

    Type:string
    Default:SunX509
    Valid Values:
    Importance:low
  • ssl.secure.random.implementation

    The SecureRandom PRNG implementation to use for SSL cryptography operations.

    Type:string
    Default:null
    Valid Values:
    Importance:low
  • ssl.trustmanager.algorithm

    The algorithm used by trust manager factory for SSL connections. Default value is the trust manager factory algorithm configured for the Java Virtual Machine.

    Type:string
    Default:PKIX
    Valid Values:
    Importance:low
  • status.storage.partitions

    The number of partitions used when creating the status storage topic

    Type:int
    Default:5
    Valid Values:[1,...]
    Importance:low
  • status.storage.replication.factor

    Replication factor used when creating the status storage topic

    Type:short
    Default:3
    Valid Values:[1,...]
    Importance:low
  • task.shutdown.graceful.timeout.ms

    Amount of time to wait for tasks to shutdown gracefully. This is the total amount of time, not per task. All task have shutdown triggered, then they are waited on sequentially.

    Type:long
    Default:5000
    Valid Values:
    Importance:low
  • topic.tracking.allow.reset

    If set to true, it allows user requests to reset the set of active topics per connector.

    Type:boolean
    Default:true
    Valid Values:
    Importance:low
  • topic.tracking.enable

    Enable tracking the set of active topics per connector during runtime.

    Type:boolean
    Default:true
    Valid Values:
    Importance:low